English Fallow budgerigar mutation
Encyclopedia
The English Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigar
Budgerigar
The Budgerigar , also known as Common Pet Parakeet or Shell Parakeet informally nicknamed the budgie, is a small, long-tailed, seed-eating parrot, and the only species in the Australian genus Melopsittacus...

s. At least three types of Fallow, the German
German Fallow budgerigar mutation
The German Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English, and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

, English and Scottish
Scottish Fallow budgerigar mutation
The Scottish Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

, all named after their country of origin, have been established, although none of these types is common. They are superficially similar, but adult birds may be distinguished by examining the eye. All have red eyes, but the German Fallow shows the usual white iris ring, the eye of the English Fallow is a solid red with a barely discernible iris and the iris of the Scottish Fallow is pink.

In an attempt to regularise the names of mutations across all psittacines, it has been proposed
by Inte Onsman

that the name Pale Fallow be adopted for this mutation. The name Dun Fallow has also been proposed, and Terry Martin suggests

Beige Fallow or Grey-Brown Fallow. But in Budgerigar circles the variety is commonly known as the English Fallow, and is the name retained here.

Appearance

In most respects English, Scottish
Scottish Fallow budgerigar mutation
The Scottish Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

 and German
German Fallow budgerigar mutation
The German Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English, and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

 Fallows are very similar. All resemble Cinnamons
Cinnamon budgerigar mutation
The Cinnamon budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. It is the underlying mutation of the Cinnamon variety and, with Ino, a constituent mutation of the Lacewing variety.- Appearance :...

, but differ in having a much weaker body colour, which results in a rather attractive mustard-yellow breast shading to green on the rump (blue in the blue series)

. The depth of the green or blue suffusion varies in individual birds, but is always more intense towards the vent and on the rump. The throat spots, head and neck striations, and wing markings are a medium brown on a yellowish ground. The cheek patches are a lighter and duller shade of violet than normal. Cocks have a greyish-purple rather than the usual blue cere. The feet and legs are pink and the beak orange.

The most obvious distinction from Cinnamons is the red eye, which in the English Fallow is a clear bright red, without a white iris ring—a beautiful and attractive feature. The eye of the German Fallow is a deep ruby-red, like an Ino's
Ino budgerigar mutation
The Ino budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. It is the underlying mutation of the Albino and Lutino varieties and, with Cinnamon, a constituent mutation of the Lacewing variety.- Appearance :...

 but a shade darker, with the usual white iris ring when adult, and the Scottish Fallow has a pink iris ring. On hatching, young English Fallows have red eyes like Inos but young German Fallow chicks have plum-coloured eyes rather like Cinnamon chicks.

The Dark
Dark budgerigar mutation
The Dark budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. It is part of the genetic constitution of the following recognised varieties: Dark Green and Olive in the green series and Cobalt, Mauve and Violet in the blue series.- Appearance :Budgerigars...

 mutation deepens the body colour of the Fallow, but the difference between the Light Green, Dark Green and Olive Fallow is far less than that between the normal Light Green, Dark Green and Olive. The Olive Fallow is "a beautiful rich golden orange shade, and the chest is deep yellow olive - a truly lovely colouring", says Cyril Rogers in The Fallows.

Fallow Greys
Dominant Grey budgerigar mutation
The Dominant Grey budgerigar mutation, often called the Australian Grey or simply Grey, is one of approximately 30 mutations affecting the colour of budgerigars. It is the basis of the Grey-Green and Grey standard varieties.- Appearance :...

 and Grey-Greens generally have darker wing markings. Opaline
Opaline budgerigar mutation
The Opaline budgerigar mutation is one of approximately 30 mutations affecting the colour or appearance of budgerigars. It is the underlying mutation of the Opaline variety...

 by itself lightens the body colour of Fallows, and in combination with Cinnamon produces a bird very similar in appearance to a Lacewing (i.e. a Cinnamon
Cinnamon budgerigar mutation
The Cinnamon budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. It is the underlying mutation of the Cinnamon variety and, with Ino, a constituent mutation of the Lacewing variety.- Appearance :...

 Ino
Ino budgerigar mutation
The Ino budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. It is the underlying mutation of the Albino and Lutino varieties and, with Cinnamon, a constituent mutation of the Lacewing variety.- Appearance :...

), with virtually no body suffusion.

Historical Notes

The English Fallow first appeared in 1937

in the aviaries of F Dervan, of Luton
Luton
Luton is a large town and unitary authority of Bedfordshire, England, 30 miles north of London. Luton and its near neighbours, Dunstable and Houghton Regis, form the Luton/Dunstable Urban Area with a population of about 250,000....

. He was a beginner to aviculture, starting in 1934 with a pair of Skyblues. He bought a pair of Greens in 1935 and bred from the two pairs. In 1936 and 1937 he intermated the descendents from these two pairs very closely, and was surprised in 1937 when seven red-eyed Fallows appeared in the nests of two of the pairs.

These red-eyed birds were inspected by C H Rogers, who suspected they might be a new variety and advised Mr Dervan to mate one of his Fallows to a German Fallow to check. This pairing was made in 1938, and from three nests eight black-eyed youngsters were bred, proving the varieties were distinct.

In 1940 English Fallows of the Blue series were produced by Mr Dervan, and at that time he had 13 Fallows and 28 split Fallows.

W P Bland, writing in the Budgerigar Bulletin in 1962
, said he "... obtained some English Fallows and by 1939 had sixty". It seems unlikely that these birds were from Mr Dervan's strain if the date is correct. There is evidence

that Scottish Fallows existed from the 1920s, and were originally called English Fallows, so it seems likely Mr Bland's were of this variety.

In the early 1960s C Warner and T G Taylor obtained English Fallows from two different sources, although allegedly from the same breeder. They found they bred only black-eyed young when cross-paired. One type had a faint iris ring while the other was completely devoid of iris pigmentation. Both varieties were distinct from the German Fallow, and they concluded that three distinct forms of Fallow existed at that time. The Fallows with the faint iris ring were good quality exhibition birds and became known as "Moffat" or Scottish Fallows after their owner, Jim Moffat.

In 1964 John Papin of California wrote

that in America no less than five distinct Fallow varieties existed. These were

  1. English Fallow, red eye, solid without ring

  2. German, red eye with ring

  3. Californian, similar to German, red eye with ring

  4. Californian, a near solid red eye type with rather fine grey markings

  5. Texas, a red eye with strong body colour


He said all were recessive and produce normals if intermated.

The numbers of all varieties of budgerigar in captivity declined dramatically during the war years and when aviculture restarted in earnest in the late 1940s English Fallows were very rare. They were originally quite small and were never very popular with breeders of exhibition birds. In the period from the 1960s to the 1980s they almost died out, but Dr Margaret Young of Rochester, Kent kept the variety alive almost single-handed, and now the variety is gaining steadily in popularity.

The name Fallow was first applied to the German Fallow
German Fallow budgerigar mutation
The German Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English, and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

 by Herr Kokemüller after Dr Steiner, who examined some German Fallow feathers microscopically, wrote to him, "It would be better to describe this form as the fallow Budgerigar rather than cinnamon." At the time it was believed that Dr Steiner used the word by analogy with fallow or undeveloped land, to mean the melanin pigment was undeveloped
, but as an alternative meaning for 'fallow' (and also for its German equivalent) is 'pale yellow' or 'light brown', it seems far more likely that it was this meaning that was intended
.
When the English Fallow appeared a few years later it was so similar in appearance to the German Fallow that for a time they were both called Fallows. Later, English, German
German Fallow budgerigar mutation
The German Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English, and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

 and Scottish
Scottish Fallow budgerigar mutation
The Scottish Fallow budgerigar mutation is one of approximately 30 mutations affecting the colour of budgerigars. At least three types of Fallow, the German, English and Scottish, all named after their country of origin, have been established, although none of these types is common. They are...

 Fallows were proved to be distinct and separate mutations by test matings made independently by T G Taylor, Mrs Amber Lloyd of Walton-on-Thames
Walton-on-Thames
Walton-on-Thames is a town in the Elmbridge borough of Surrey in South East England. The town is located south west of Charing Cross and is between the towns of Weybridge and Molesey. It is situated on the River Thames between Sunbury Lock and Shepperton Lock.- History :The name "Walton" is...

 and Frank Wait
, and qualified names were then introduced to distinguish them. It was found that birds of any two of the mutations produced only normal black-eyed young when paired together.

Genetics

The English Fallow is an autosomal mutation causing recessive
Recessive
In genetics, the term "recessive gene" refers to an allele that causes a phenotype that is only seen in a homozygous genotype and never in a heterozygous genotype. Every person has two copies of every gene on autosomal chromosomes, one from mother and one from father...

 changes to the form of the melanin pigment. There is no universally accepted genetic symbol for either the locus
Locus (genetics)
In the fields of genetics and genetic computation, a locus is the specific location of a gene or DNA sequence on a chromosome. A variant of the DNA sequence at a given locus is called an allele. The ordered list of loci known for a particular genome is called a genetic map...

 or mutant allele, so the simple symbol fe+ will be adopted here for the wild-type allele
Allele
An allele is one of two or more forms of a gene or a genetic locus . "Allel" is an abbreviation of allelomorph. Sometimes, different alleles can result in different observable phenotypic traits, such as different pigmentation...

 at this locus, and the symbol fe for the English Fallow mutant allele, in keeping with the most widely used name in budgerigar circles.

In its visual effect, the English Fallow mutation is recessive to its wild-type allele, so a bird possessing a single English Fallow allele (the heterozygote, fe+/fe) is identical in appearance to the wild-type light green. That is, the presence of a single wild-type allele is sufficient to permit the full production and normal distribution of the black melanin pigment. Among the budgerigar fancy such a bird is said to be a Light Green split English fallow, usually written Light Green/English fallow.

In a bird which has two English Fallow alleles (the homozygote, fe/fe), the lack of the wild-type allele means that normal black melanin pigment cannot be produced. Instead a pigment giving a brown appearance is substituted, resulting in brown markings where black would appear in the Normal.

External links

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